Thermal performance prediction and energy conservation potential of earth air tunnel heat exchanger for thermal comfort in building

Abstract

In this communication, thermal performance of building integrated “Earth Air Tunnel Heat Exchanger” (EATHE) has been studied for a composite climate of Delhi. Mathematical model and building thermal simulation software (Energy Plus) are used for prediction of indoor air temperatures. The predicted results are validated through experimental results. Energy conservation potential both for heating and cooling of EATHE has been evaluated for winter and summer months in a specific year. Quantitative assessment of CO2 mitigation has also been computed. It is observed that Coefficient of performance (COP) of EATHE is found between 6.3–13 during summer and 6.8–9.5 during winter season. The maximum drop in air temperature across the earth air tunnel is found to be 8.7 °C with air velocity of 2.69 m/s during peak summer and during winter season the room air temperature is raised by 5–7 °C. On the other hand, the system is capable of maintaining room temperature in the range of 27–30 °C during peak summer when outdoor temperature are in the range of 33–41 °C. EATHE integration with building can significantly reduce the electrical power consumption by 96.63 MWh annually, needed for space heating and cooling load. It is discovered from the study that this EATHE has potential of reducing global warming 8 by substantially mitigating CO2 to the tune of 95 tonnes annually.